But the European Commission, the EU's executive arm, disagreed that Merkel's announcement would lead to paralysis, a commission official said.

"Angela Merkel's decision was expected. She had foreseen it and it changes nothing. The chancellor will not leave right away," the official told AFP on condition of anonymity.

Sudha David-Wilp, deputy director of the German Marshall Fund's Berlin office, also noted that Merkel's departure was not a surprise and appeared to be orderly.

"I don’t see chaos or instability for Europe because this is going to be a very slow departure," David-Wilp told AFP from the United States.

"Right now it is not in anybody's interest for the grand coalition to split apart in Berlin," she added in reference to Merkel's ruling coalition with the centre-left SPD party.

'Serious internal crisis'

Other analysts underscored uncertainty over who -- from loyal allies to fierce critics -- will replace Merkel as head of the centre-right CDU party in December and secure a chance to succeed her as chancellor.

"If it's Annegret Kramp-Karrenbauer, it will be rather a good thing to revive the EU," Schuman Foundation Director Jean-Dominique Giuliani told AFP.

"She is close to France and is very European. She will be more active than Merkel, who always played in the background," he added.

"If Annegret Kramp-Karrenbauer assumes the party chairmanship, there's still a chance the chancellor can stay on the job until 2021," Rappolt said.

If not, "it will be the end," he warned.

Such uncertainty comes at a bad time.

"Europe is experiencing a serious internal crisis," an official from an EU member country noted.

"There is a lack of leadership in Europe. Most of the leaders are in trouble," the official told AFP on condition of anonymity.

French President "Emmanuel Macron has tried to give new impetus, but his initiatives have not found much support," Rappolt remarked.

Merkel herself has done little to revive Europe, Maillard said.

"The French-German engine did not start because France never had a guarantor in the chancellor. Angela Merkel always temporised, was always on the defensive," he said.

Schuman Foundation president Guillani suggested "now that her authority is dented, tongues will loosen. I think her balance sheet will be pretty negative."